FUD Zilla writes Intel's 2011 Cedar-Trail M Atom processors will lower the total system TDP all the way down to 5W. Not all of these systems will require active cooling, and this will give system builders more freedom to create more compact designs.
This is definitely something that might get you excited as the current N4x0 generation of Atoms have 7W to 8 W TDPs. With the introduction of new Atoms, netbooks will become fanless, at least some of them, so there might be some new form factors and it will bring the sleeker designs to market.
This should also mean that battery life will get at least slightly better and that nebooks ought to become cooler and slimmer.